With known surgical microscopes, for example with the M841 of the Leica company (see brochure, “The Leica M841—The Ultimate Surgical Microscope System for Ophthalmology,” Publication no. 10 M1 841 Oen, printed VII.2000), surgery is performed on and below the retina (fundus) when ophthalmological diseases are present. The region extends from the macula to the ora serrata.
There also exist retinal diagnostic devices specifically for this sector, for example the retinal diagnostic device of Medibell Medical Vision Technologies Ltd., Haifa, Israel, referred to (in a brochure without publication information) as the “Panoret 1000—Wide-Angle Digital Retinal Camera.” Retinal diagnostic devices in general are also commonly referred to as “retinal cameras” or “fundus cameras,” and are produced by a number of manufacturers.
Retinal cameras are used for the diagnosis of corresponding diseases, and are sufficiently known.
The basic principle of such retinal cameras is that the observation beam path is guided through the patient's pupil together with the illuminating beam path.
Guidance of the observation and illumination beam paths together through the patient's pupil is, however, very difficult to implement. Compromises are therefore accepted.
The Medibell company developed the digital retinal camera indicated above, in which the observation beam was separated from the illumination beam so that these difficulties could thereby be circumvented. Observation is performed using a special optical system in direct contact with the patient's eye. Illumination is conveyed into the patient's eye in transscleral fashion (i.e. through the sclera of the eye) using a fiber illumination system.
The light source comprises three color diodes that are pulsed. The highresolution digital BW (black-and-white) camera is triggered simultaneously with the three colored light pulses. Image processing of the BW image yields an outstanding high-resolution color image on the color monitor or alternatively, given appropriate real-time processor performance, a live image. A similar arrangement, although not with pulsed color diodes but rather with a white-light source with color filter selection, is known from U.S. Pat. No. 6,309,070.
For a surgeon, it is desirable to use a retinal diagnostic device during an operation as well, i.e. not only for separate diagnosis. The reason is that utilization of the retinal diagnostic device is extremely cumbersome, since surgery using the surgical microscope must be interrupted in order to move the retinal diagnostic device over the patient's eye in order to make the desired (interim) diagnosis. The retinal diagnostic device must then, if applicable, be exchanged once again with the surgical microscope. Another desire on the part of ophthalmic surgeons is to receive from the diagnostic device not a separate, monoscopic image of the retina, but rather an enlargeable and, if applicable, stereoscopic one.